‘The fight is off’: Furious Conor McGregor cancels UFC rematch with ‘f***ing braindead’ Dustin Poirier over charity donation claim

Conor McGregor has publicly told Dustin Poirier that their trilogy UFC fight is off and he will "fight someone else" on their scheduled date of July 10, calling his rival a "fool" and a "f***ing brain-dead hillbilly" on Twitter.

The former champion became embroiled in a row over a $500,000 charitable donation after Poirier claimed that McGregor's generous pledge, made before their UFC 257 scrap, had not materialized.

Fans turned on McGregor after Poirier accused him of "ghosting" attempts to arrange payment, leading to the Irishman explaining that he had not done so because he wanted to be sure that the money would reach its intended causes.

Now a clearly-furious McGregor has torn in to Poirier on Twitter, insisting that he had no coherent scheme to use the money while launching a string of insults at him before calling their bout off.

"You’re ripped, you inbred hillbilly," McGregor wrote, venting in front of his fanbase of more than 8.5 million on Twitter.

"Why do you wink with your ears? You f***ing brain-dead hillbilly. $500,000 with no plan in place. Ye hang tight. Fool. You must be new to money.

"The fight is off, by the way. I’m going to fight someone else on the 10th. Good luck on your old contract, kid."

It is not clear whether there are any clauses in the contract for the fight that would allow McGregor to rip up the deal of his own will, but the exchange appears to have ended any goodwill after the pair exchanged warm words over the pledge in a press conference and Poirier's wife, Jolie, thanked McGregor in his locker room after her husband knocked him out in January.

"My team does their due diligence to make sure every donation meets the mark," ranted McGregor, mystifyingly calling Poirier a "shooting ass shelling ass b***h" who made "little b***h kicks from a shell."

"My generosity is known. You will pay with your brain for this attempt at smearing my name. Good luck when you’re caught. You’re f****d."

Poirier coolly replied "Ok", accompanying his response with a clip of McGregor sprawled against the octagon following his stunning defeat.

When 'The Diamond' was told by a McGregor associate that he had made a "low move" and asked about his claims a couple of hours beforehand, Poirier responded: "His team hasn't responded to our emails about anything involving my foundation after they reached out to us originally."